Children exposed to high levels of ‘forever chemicals’ in womb more likely to be obese, study finds

Children exposed to high levels of forever chemicals in the womb are more likely to be overweight or obese, a government-funded study has found.

Researchers at Brown University found that the risk posed by forever chemicals starts before birth, setting children up for later health problems.

Per- and polyfluorinated substances (PFAS) have been dubbed ‘forever chemicals’ because they are nearly indestructible.

PFAS have been standard in producing everyday household products, from nonstick pans and food packaging to fire extinguisher foam.

Previous studies have found that consuming forever chemicals contributes to weight gain because they can disrupt hormone regulation. 

Exposure to PFAS has also been linked to a multitude of concerning health issues, including infertility, metabolic disorders, kidney disease and certain types of cancer.

Their findings were based on eight research cohorts in different parts of the US and other demographics.

The study collected data over two decades from 1,391 children aged between two and five years and their mothers.

The participants were from California, Illinois, Massachusetts, Colorado, New Hampshire, Georgia and New York. 

The researchers examined the levels of seven different PFAS chemicals in blood samples collected from mothers while pregnant. They also calculated each child’s body mass index (BMI).

The researchers found that higher levels of PFAS in the mother’s blood during pregnancy were linked to slightly higher BMIs in their children.

Each doubling in perfluroundecanoic acid was associated with a 10 percent increased risk of the child being overweight or obese.

Each doubling of N-methyl perfluorooctane sulfonamido acetic acid was linked to a six percent higher risk of the child being overweight or obese.

This connection was seen even at low levels of PFAS exposure, said senior author Joseph Braun, a professor of epidemiology and director of the Center for Children’s Environmental Health at Brown’s School of Public Health.

He said: ‘The fact that we see these associations at relatively low levels in a contemporary population suggests that even though PFAS usage in products has decreased, pregnant people today could still be at risk of harm. 

‘This means, according to our findings, that their children could also be at risk of PFAS-associated harmful health effects.’

The researchers noted that the link between PFAS and BMI is ‘biologically plausible’.

The study paper said: ‘PFAS can readily pass through the placenta and move from the maternal to the fetal circulation, with PFHxS having the highest placental transfer rate and PFNA, PFDA, PFUnDA potentially having low placental transfer rates.’

PFAS activate a group of nuclear receptor proteins, affecting adipocyte programming (how energy is stored in the body) and possibly causing adipogenesis (forming fat cells), thereby increasing fat mass.

PFAS may also disrupt thyroid function and possibly decrease and increase levels of different thyroid hormones, which may increase fatty tissue in the body.

The study was published in the journal Environmental Health Perspectives.

Studies suggest that more than 97 percent of Americans now have PFAS chemicals circulating in their blood.

But US states are still only just waking up to the threat, with Minnesota set to become the first to ban them completely by 2025.